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PENGEMBANGAN DETEKTOR SIGNAL RADIO MULTI CHANNEL UNTUK RADIO TRACKING ROKET MENGGUNAKAN LOGARITMIK AMPLIFIER Zain, Satria G.; Susanto, Adi; Widodo, Thomas Sri; Widada, Wahyu; Kliwati, Sri
Indonesian Journal of Aerospace Vol. 6 No. 2 (2008): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

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Abstract

Pengukuran kuat signal radio telemetri roket sangat penting dilakukan untuk mengetahui hubungan kualitas signal dan data yang diterima. Power meter ini juga dapat diaplikasikan untuk deteksi perubahan sudut elevasi dan azimuth trayektori roket dengan menggunakan array antena yagi yang telah dikembangkan metodenya. Power meter radio mempunyai rentang pengukuran yang sempit, sehingga terjadi saturasi untuk pengukuran radio dengan power yang cukup besar. Tulisan ini membahas desain dan pengembangan power detektor untuk mendeteksi signal radio pada sistem telemetri roket dengan maksimum pengukutan 1 watt dan dapat diubah sesuai dengan kebutuhan. Signal power meter ini berbasis logarithmic amplifier dengan lebar band sampai dengan 100 db dengan ketelitian 0.02 dB.
ALGORITMA DETEKSI FREKUENSI DTMF MENGGUNAKAN KORELASI SILANG UNTUK TELEKOMANDO WAHANA TERBANG (DTMF FREQUENCY DETECTION ALGORITHM USING CROSSCORRELATION FOR VEHICLE TELECOMMAND) Kliwati , Sri
Indonesian Journal of Aerospace Vol. 14 No. 1 Juni (2016): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.jtd.2016.v14.a2942

Abstract

In general, the frequency DTMF detection algorithm using FFT (Fast Fourier Transform) and Goertzel Algorithm. However, in certain circumstances a more suitable signal detected by the other algorithms. For example in a non-periodic signal as the measurement sensors for flight vehicle. The purpose of this study is to develop a system telecommand for flight vehicle. And this paper discusses the frequency DTMF (Dual Tone Multi Frequency) detection method using cross correlation algorithm and data-base DTMF. The simulation results show the frequency detection successfully carried out in accordance with the accuracy of the data-base created (1 Hz) to change the frequency of zero to 1700 Hz (DTMF frequency limit).
PENINGKATAN REOLUSI PERHITUNGAN FREKUENSI GELOMBANG SINUS MENGGUNAKAN FFT (IMPROVING CALCULATION RESOLUTION OF SINE WAVE FREQUENCY USING FFT) Kliwati , Sri
Indonesian Journal of Aerospace Vol. 13 No. 1 Juni (2015): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

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Abstract

Perhitungan perubahan frekuensi sinyal sinus sangat penting untuk aplikasipada intrumentasi. Seperti pada sistem Doppler yang juga memerlukan perhitunganfrekuensi keluaran berupa gelombang sinus. Tulisan ini membahas peningkatanresolusi perhitungan perubahan frekuensi gelombang sinus berbasis algoritma FastFourier Transform (FFT). Penambahan waktu sampling data dapat meningkatkanresolusi frekuensi dengan signifikan, tetapi sampling data menjadi lebih rendah. Padaaplikasi frekuensi Doppler 440 MHz resolusi kecepatan sekitar 6.8 m/detik dengansampling data 10 Hz. Resolusi dan sampling data ini harus disesuaikan dengankecepatan dan durasi terbang roket agar optimal dalam pengukurannya
PENERAPAN LOW PASS FILTER UNTUK MEMPERBAIKI HASIL ESTIMASI SUDUT PADA SISTEM RADIO TRACKING ROKET Zain, Satria Gunawan; Susanto, Adhi; Widodo, Thomas Sri; Kliwati, Sri; Widada, Wahyu
Indonesian Journal of Aerospace Vol. 8 No. 1 Juni (2010): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

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Abstract

Radio tracking system can be applied to track the position of a rocket and is potential to be developed to replace the GPS technology. This system is used to estimate the direction angle (azimuth and elevation) of transmitter source. In measurement and trial there are many noises that cause the results of angle estimation are not accurate. These noises can be obsreved from the value of the angle estimation varied for a fixed measurement point. This is caused by the interference on the received sinyal. This paper discusses the application of low pass filter to eliminate noises in the radio receiver system. Experiment results show that the variation of estimates angle becomes 1600 times smaller compared to the one without filter
ON-BOARD FUNDAMENTAL FREQUENCY ESTIMATION OF ROCKET FLIGHT EXPERIMENTS USING DSP MICROCONTROLLER AND ACCELEROMETER Syah, Agus Harno Nurdin; Kliwati, Sri; Widada, Wahyu
Indonesian Journal of Aerospace Vol. 7 No. 1 Juni (2009): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

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Abstract

Fundamental frequency vibrasi roket pada saat terbang sangat penting diukur untuk pengembangan sistem elektronik maupun mekanik muatan roket. Tulisan ini membahas metode pengukuran fundamental frekuensi tersebut dengan menggunakan sensor accelerometer dan 32 bit DSP (Digital Signal Processor) microcontroller. CPU ini digunakan untuk akuisisi data dan perhitungan algoritma DFT (Discrete Fourier Transform) serta algoritma penentuan frekuensi fundamentalnya. Deteksi fundamental frekuensi berbasis envelope (lowpass filter) spektrum frekuensi. Sistem yang telah dibuat dapat dikombinasikan dengan radio modem untuk pengiriman data dengan kecepatan serta sampling rate yang cukup tinggi. Maksimum frekuensi yang dapat diestimasi hingga 2 kHz, cukup untuk parameter roket.
RANCANGAN DAN ANALISA ANTENA DI PERMUKAAN BADAN ROKET Kliwati, Sri; Widada, Wahyu
Indonesian Journal of Aerospace Vol. 2 No. 1 (2004): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.jtd.2004.v2.a791

Abstract

The antenna telemetry is usually placed in the body of LAPAN rocket for the launching campaign, which affected to the quality of radio communication. Especially, such effect increas the antenna overshadow to the surface of body rocket, which not influenced to the aerodynamic of rocket. This antenna was made by using the PCB plate with size of 1 cm width and 1 per 2 also 1 per 4 length for the frequency of 900 MHz
METODE KALIBRASI TIME DIFFERENT OF ARRIVAL TDOA UNTUK SISTEM PASSIVE RADAR TRAYEKTORI ROKET Widada, Wahyu; Kliwati, Sri
Indonesian Journal of Aerospace Vol. 5 No. 2 (2007): Jurnal Teknologi Dirgantara
Publisher : BRIN Publishing

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Abstract

Design passive ranging base on radio with Time Different of Arrival TDOA (passive RADAR) have been developed for the application of tracking rocket trajectory. Calibration of the passive RADAR can be done in launching site for obtaining optimal position, however it is also require to be done in laboratory for testing the system algorithm. This article describes the calibration method of time delay calculation in laboratory using antenna cable with various of lengths. We obtain an accurate correlation results between time delay from measurement of oscilloscope and calculation TDOA with cross-correlation method. This method is practical and effective for calibration system in the development of passive RADAR. Keywords: TDOA, Passive RADAR, Trajectory rocket, Calibration method, Cross-correlation.-